You can replace a Hyundai key fob battery yourself in about two minutes with a coin and a replacement battery

Hyundai key fobs use a standard coin-cell battery that you can buy at any drugstore, supermarket, or hardware store for a few dollars. The fob itself is designed to open without tools — you just need a flat coin to pry the two halves apart, swap out the old battery for a new one, and snap it back together. The whole job takes longer to find the right battery type than to do the replacement.

The battery type varies slightly by model year and fob design, but most Hyundai fobs use either a CR2032 or CR2025 battery. You can find the correct type by checking your owner's manual, looking at the battery compartment itself once you open the fob, or calling a Hyundai dealer with your vehicle identification number (VIN). Once you have the right battery, the replacement is the same across all Hyundai models.

Key Takeaways

  • Most Hyundai key fobs use a CR2032 or CR2025 coin-cell battery, which you can buy at any pharmacy or grocery store for under five dollars.
  • Open the fob by inserting a flat coin into the slot on the edge and twisting gently until the two halves separate.
  • Note which side of the battery faces up before you remove it, then insert the new battery the same way and close the fob.
  • If the fob still does not work after you replace the battery, the problem may be a worn contact or a damaged circuit board, not the battery itself.

Finding the correct battery type for your Hyundai fob

The easiest way to know which battery your fob needs is to open it first and look at the old battery itself. Once the fob is open, the battery will be sitting in a small metal holder, and the type and voltage are printed on the flat side. Write down the number — it will be something like CR2032 or CR2025 — and take a photo with your phone so you have it when you shop.

If you want to know before you open the fob, check your owner's manual in the key fob or remote control section. Hyundai also prints the battery type on the back of some fobs, though not all. If neither of those works, call your local Hyundai dealer with your VIN and model year, and they can tell you over the phone. Do not assume all Hyundai fobs are the same — a 2015 model may use a different battery than a 2020 model.

How to open the Hyundai key fob safely

Look at the edge of your fob for a small slot or seam running along the side. This is where the two halves of the fob meet. Insert a flat coin — a dime or penny works — into that slot and twist gently, as if you were opening a battery compartment on a remote control. You should feel the two halves start to separate. Do not force it; if it does not give after gentle pressure, you may be in the wrong spot.

Once the halves are loose, use your fingernail or the coin to pry them apart the rest of the way. The fob will split into two plastic pieces, and you will see the battery sitting in a small metal holder in the center. The battery is usually held in place by the metal contacts on either side, so it should not fall out on its own. If it does, pick it up carefully and note which side was facing up.

Removing the old battery and installing the new one

Before you touch the old battery, take a moment to notice which side is facing up — the flat side with the number printed on it, or the rounded side. This matters because coin-cell batteries only work in one direction. Gently pry the old battery out of the metal holder using your fingernail or the edge of a coin. It should come out easily without any force.

Once the old battery is out, place the new battery into the same holder with the same side facing up as the old one was. The metal contacts on either side of the holder should grip the battery snugly. If the battery sits loose or falls out when you tilt the fob, it may be the wrong size, or the contacts may be worn. Close the fob by pressing the two halves together until you hear or feel a click. Test the fob by pressing a button — the light should come on, and the car should respond if you are in range.

What to do if the fob still does not work after replacing the battery

If you installed a new battery and the fob still does not work, the problem is usually not the battery itself. The most common culprit is worn or corroded metal contacts inside the fob. Over time, the small metal springs that touch the battery can become dirty or bent, breaking the electrical connection even with a fresh battery in place.

You can try cleaning the contacts by gently rubbing them with a pencil eraser or a dry cloth, then reinstalling the battery. If that does not work, the circuit board inside the fob may be damaged, or the fob may straightforward be at the end of its life. At that point, you have two options: buy a replacement fob from a Hyundai dealer or a third-party supplier, or have a dealer reprogram an aftermarket fob to your vehicle. Dealer fobs are more expensive but may provide to work; aftermarket fobs are cheaper but quality varies.

Where to buy replacement batteries and what to expect to pay

CR2032 and CR2025 batteries are among the most common coin-cell batteries made, so you can find them almost anywhere. Pharmacies like CVS and Walgreens stock them in the watch and battery section. Grocery stores usually carry them near the checkout or in the health and beauty section. Hardware stores like Home Depot and Lowe's have them in the electrical aisle. Online retailers like Amazon sell them in bulk packs, which is cheaper per battery if you have multiple devices that use them.

A single battery typically costs between one and three dollars at a pharmacy or grocery store. Bulk packs of four to ten batteries cost three to eight dollars total, or about fifty cents to a dollar per battery. Dealer batteries are more expensive — usually five to ten dollars per battery — but they are the same product as what you buy elsewhere. There is no advantage to buying from the dealer except convenience if you are already there for service.

Frequently Asked Questions

Can I use a different battery type if I cannot find the exact one?

No. CR2032 and CR2025 look similar but have different thicknesses and voltages, and using the wrong one can damage the fob's circuit board or cause it to malfunction. Always match the number printed on the old battery or listed in your manual. If you cannot find the exact type locally, order it online rather than substituting.

How often do I need to replace the battery?

Most Hyundai key fob batteries last between three and four years with normal use. If you use the fob heavily — pressing buttons many times per day — the battery may wear out sooner. You will notice the range getting shorter or the light dimming before the battery dies completely, so you usually have warning.

Will replacing the battery erase my fob's programming?

No. Changing the battery does not affect the programming that links your fob to your car. The fob will work exactly as it did before once you install the new battery. You only need to reprogram a fob if you buy a new one or if the fob stops responding even after a battery replacement.

What should I do with the old battery?

Most retailers that sell batteries also take old ones back for recycling at no charge. CVS, Walgreens, Best Buy, and Home Depot all have battery recycling programs. You can also check Earth911.com or call your local waste management office to find a drop-off location near you. Do not throw batteries in the trash.

Can I replace the battery in a Hyundai smart key or push-button fob the same way?

Smart keys and push-button fobs have a slightly different design, but the battery replacement process is the same. Look for the slot on the edge, use a coin to open it, and swap the battery. The battery type may differ — some smart keys use CR2032, others use CR2016 — so check your manual or the old battery before you buy a replacement.